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  <title>Document</title>
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<body>
  <script>
    var numJewelsInStones = function (jewels, stones) {
      let num = 0
      for (let i = 0; i < stones.length; i++) {
        for (let j = 0; j < jewels.length; j++) {
          if (stones[i] == jewels[j]) {
            num++
            break
          }
        }
      }
      return num
    };
    console.log(numJewelsInStones("z", "ZZ"))
  </script>
</body>

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